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EXTENSION LADDER. 4 No. 307,734. Pate ted Nov. 4, 18:84..

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ASAHEL TODD, F PULTNEYVILLE, NEV YORK.

EXTFNSHON=LADER SPECIFICATION forming part of Letters Patent No. 307,734-, dated November ll, 1884:.

(No model.)

To a/Z when?, t nfl/ay concern.-

Be it known that I, AsitHnL TODD, acitizen of the United States, residing at Pultneyville, in the county of lVayne and State ot' New York, have invented a new and useful Extension-Ladder of which the following is a specification. v

My invention relates to improvements in extension-ladders, first, in the use of a conipensating spiral spring to regulate the contraction and expansion of the ropes used in raising or lowering the upper section second, a flexible spur pivoted to a counterbalancehook to allow the upper section to be lowered without swinging the hook; third, an adjustable claw attached to the upper part of the lower section, to be used when required as a roofladder, fourth, an iron or wooden brace fastened to the sides of the lower section to strengthen and stiffen the lower section. I attain these objects by the use of the several parts illustrated in the accompanying drawings, making a part of this specification, in which- Figure lis a perspective view of the ladder complete. Fig. 2 shows the position of the flexible spur when descending past the rounds ot' the lower section. Fig. 3 represents the spur detached, and the dotted line showing the position of the spur when the ladder is being extended or the hook fastened to a round of the lower' section. Fig. 5 shows the manner of tightening the brace-rod. Fig. 4 is a toothed wheel and cap attached to the top of the upper section.

Like letters of reference refer to siniilar parts in the several figures.

To enable others to use iny invention I will describe the inanner of constructing the saine.

The sides of the lower section, A A, Fig. l, should be spread at the bottoni to forni a wide base, and from the bottoni inay contract to the lower' clips, B B, where they niust be parallel. rlhc clips l Il are inade of heavy band-iron riveted to the inner side of the lower section, A A, and bent to conform to the width and thickness of the upper-section sides C C. In the center ofthe upper round ofthe lower section fasten the pulley a. rlhe upper-section sides C C must be parallel and narrow enough to slide freely between the sides of the lower section and to nieve easily under the curved ends of the clips B B.. The cap K, Figs. l, 5, and G, is a piece of band-iron with a hole punched near one end, then turned over, forrning a right angle, as shown in Fig. 5. l A channel is cut in the sides of the lower section at the top and near the upper edge of the side A A. The cap is then fastened over the channel with the short angle over the end of the side A, as shown in Figs. l and 6. At ce, Fig. l, bore a hole; then pass through the hole the rod H, having on the inside end a head to prevent it from drawing through. Now bend the rod upward, passing the end under the cap K in the channel and through the hole punched in the cap. rlhis end ofthe rod should have a thread cut to screw a nut down firmly upon the cap. The props b b should have a notch for the rod H to rest in, andl should be thick enough to bend the rods outward, as shown in Fig. l, and downward, even with the lower edge of A, as shown in Fig. 6. These props niay be made of wood or iron and should be secured to the sides A near or over the rounds. The claw f, Figs. l and 6, is a piece of iron fastened at one end by a screw or rivet to the side A. When the lower section is used as a roof-ladder, the claw f is turned against the stop g', forming a right angle with the ladder and conforming to the ridge and roof of the building. rEhe hook E is niade of cast-iron, curved and counterbalanced, so it will readily hook over a round ot' the lower section and retain the upper section in position, as represented in Fig. l. The

hook has a hole castin the ccnterlarge enough to allow it to swing easily upon the lower round of the upper section. The hook has a flexible spur, U, pivoted to the center of the J hook, which prevents it from fastening to a round when descending, as shown. As the upper section is being raised, the curved back edge of the hook E alternately strikes the rounds of the lower section, and then gives backward by turning on its round, so as to pass by, ils weighted end always causing the hook to resume its position. The spur C, being pivoted, also gives backward as it strikes against the rounds of the lower section, and after giving backward as far as it can causes the hook E to partially revolve, so as to allow IOO vIO

the spur to slip past. Wlhen the upper section has been raised high enough, the spur serves to guide the hook, so that it will catch over any desired round, and thus serve to assist in supporting the upper section in place, passing a round in Fig. 2. After passing a round, the spur falls tothe position represented by the dotted line c', Fig. 8.

I am aware that counterbalanee-hooks for extension-ladders have been used with the spur cast solid with the hook; vbut hooks cast in one piece nearly revolve when descending,

' and are apt to strike the cou liter-balance d, Fig.

3, upon a round, thereby breaking the round or endangering the hook. The flexible spur, when passing rounds in descending, merely turns up to the hook, swinging thc hook slightly.

rlhe toothed wheel `W, Figs. l and 4, is made of cast-iron, with an axle, upon which it revolves. The cap h, Fig. Ll, has a hole cast or punched suitable for the axle of the Wheel V. Bore a hole near the top and lower edge of C, in it place one arln of the axle of the wheel XV, and screw thc cap h' over the other axle, as represented in Fig. l. The wheels NV should project below the edge of the sides C G, so the weight of the ladder-will rest upon them when against a building.

J, Fig. 1,- is a spiral spring securely fast'- ened to the round ot' the upper section, as at L. YThe lower part of the spring should closely coil around the shank oi' the pulley m.

To adjust the ropes used in raising and low-` ering the upper section, lay the lower section upon benches with the clips B B upward. Place the upper section on the rounds of the lower section and under the curved end of the clips B B. Tie the rope c to the second round from the bottom of the upper section at f, pass the free end of the rope between the rounds of the upper and lower sections, through the pulley m, and under the rounds of the lower section, bore a hole through the windlass D at pass the rope through, and tie a knot. By turning the crank a it will wind the rope around the windlass and extend the ladder to the extreme limit desired. Tie the second rope, Z), to the round f of t-he upper section, pass the free end through the pulley n and between the rounds of the upper and lower sections to the windlass D, bore a hole at c, pass the rope through, and tie a knot.

rlhe contraction or expansion ofthe ropesis equalized by the spiral spring J.

What I claim, and desire to secure by Letters Patent, is-

1. The combination,with thesliding sections of an extensible ladder, of the ropes b c, passing over the pulleys m n, attached to said seetions, respectively, the pulley m being provided with a spring, J, substantially as shown.

2. The combination, with`the sections or" an extensiolrladder and a mechanism for raising and lowering the upper section, ot' counterbalanced hooks upon the rounds of the upper section, and the pivoted spurs which are at tached to the hooks, the said hooks being adapted to partially rotate upon thc rounds of the ladder, substantially as described.

3. The combination ot the adjustable claw f with the sides A of the ladder, substantially as set forth.

4. The combination ofthe brace H and cap K with the pieces b', substantially as specified.

ASAHEL TODD.

Witnesses:

ALBERT A. PAILLisrEn, ABR. H. DUNNING.

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